A vehicular occupant determination apparatus includes a load detection portion, an occupant determination portion, an acceleration detection portion, a transition prohibition portion, and a transition permission portion. The transition permission portion detects whether an acceleration increases or decreases a load, and sets a transition permission state even during the transition prohibition state. In the transition permission state, a determination result of a first occupant type is permitted to transit to a determination result of a second occupant type with a smaller load than the load of the first occupant type when the acceleration increases the load, and the determination result of the first occupant type is permitted to transit to a determination result of a third occupant type with a greater load than the load of the first occupant type when the acceleration decreases the load.